A conventional collapsible baby bed shown in FIGS. 20 and 21. The bed includes an upper frame 11, four feet 12, four foot bases 13, a lower frame 14, four corner joints 15, four bending joints 16, a bed cover 17 and a bed mattress 18.
The upper frame and the lower frame are connected together with the four feet 12, the four feet extending respectively between the four corner joints 15 and the four foot bases 13. Each of four horizontal sides of the upper frame 11 are made of two rods connected together by a bending joint 16 at the central portion of the side, and the bending joints 16 are able to be bent down to a certain angle, or to be locked straight. The bed cover 17 covers the whole frame and the bed mattress 18 is laid on a bottom formed by the lower frame. The bed mattress has enough thickness and strength for a baby to sit, stand or lie thereon. The cover is made of four pieces bendably sewn together and a hook means is affixed on a front end thereof, so as to wrap the bed frame in a collapsed state, as shown in FIG. 19, for carrying and storage.
The quality of a collapsible baby playing bed depends upon the materials used for forming the bed frame, the collapsible structure of the upper and lower frames, and the stability and safety of the whole frame after it is spread out. In using the bed, it should have enough safety and stability for a baby to play or sleep therein. For collapsing, the lower frame should be pulled up easily by a pull slip and then the upper frame should be folded to the center. The lower frame of the conventional baby playing bed, shown in FIG. 21, has a structure where components are pivotally connected with other components so as to bend a little inward, so that it may not collide with the upper frame. The lower frame has four connectors 19 and a supporter 191 for collapsing, spreading and supporting the whole frame and a mattress.
The lower frame of the conventional collapsible baby bed just described has been found to have the following undesirable disadvantages:
1. When the whole bed is spread out, it is supported only at the center and at four corners, and especially, there is not enough support for the bed mattress, which is easily forced to deform or break because of the weight of a baby playing in it; and,
2. The bending joints of the upper frame are not provided with a safe means for preventing displacement, so should a baby in the bed touch and press one of the bending joints by accident or curiosity, the upper frame would be collapsed, causing danger to the baby.